While scuba diving, a diver needs to know scuba tank related status information, such as scuba tank air pressure. Typically, a pressure gauge that measures air pressure is coupled to the scuba tank. The diver may look at the pressure gauge during a dive to see the amount of air pressure in the scuba tank and determine an amount of time he has left for diving. However, the diver may get distracted and not check the pressure gauge as often as he should, or he may have trouble seeing the gauge. This could lead to the diver not adequately preparing to return to the surface at the correct time.